d and f BLOCK ELEMENTS

What is the color of the tetrahedral manganate ion?

• Green
• Blue
• Purple
• Yellow

What is the main purpose of the electrolytic oxidation step in the commercial preparation of KMnO4?

• To reduce permanganate to manganate
• To convert manganate (MnO4^2-) to permanganate (MnO4^-)
• To precipitate MnO2
• To neutralize the solution

What is the oxidation state of manganese in the K2MnO4 formed during the preparation of potassium permanganate?

• +4
• +6
• +7
• 0

What is the main oxidizing agent used in the fusion step for preparing potassium permanganate according to the text?

• Only KNO3
• Either air or KNO3
• Only air
• Hydrogen peroxide

What type of reaction is involved when manganate (MnO4^2-) converts to permanganate (MnO4^-) and manganese dioxide (MnO2)?

• Combination
• Decomposition
• Disproportionation
• Neutralization